The recent failure of a SpaceX rocket’s upper stage engine, which resulted in the loss of 20 Starlink internet satellites in a low, non-survivable orbit, has prompted an investigation by the Federal Aviation Administration. This incident is likely to cause a delay in at least one, and potentially two, upcoming piloted flights of the company’s Falcon 9 rockets.
An unfortunate Incident has occurred, resulting in the
termination of a remarkable streak of 344 consecutive successful Falcon 9
flights since 2015. The Federal Aviation Administration (FAA), the regulatory
body responsible for licensing commercial launch operations within the United
States, has issued a statement on Friday, mandating a joint investigation into
the failure before granting clearance for the Falcon 9 to resume its
operations.
“A return to flight is based on the FAA determining that any
system, process or procedure related to the mishap does not affect public
safety,” the FAA said. “In addition, SpaceX may need to request and receive
approval from the FAA to modify its license that incorporates any corrective
actions and meet all other licensing requirements.”
In the meantime, the planned July 31 launch of entrepreneur
Jared Isaacman and three crewmates on a commercial flight that will include the
first spacewalk by private citizens — Polaris Dawn — is in limbo.
The failure also could impact NASA’s plans to launch its
next long-duration crew to the International Space Station. Liftoff of the Crew
9 mission currently is targeted for around Aug. 19, but that assumes the SpaceX
failure investigation is complete by then and that NASA concurs with the
findings.
For his part, Isaacman was not deterred, posting a note on
social media that he and his crew, including two SpaceX employees, have full
confidence in the Falcon 9.
“SpaceX has an incredible track record with Falcon 9,” he
said. “I can say from personal experience they are very transparent when issues
arise. I have no doubt they will arrive at a cause quickly and ensure the most
cost-effective and reliable launch vehicle keeps delivering payload to orbit.
“As for Polaris Dawn, we will fly whenever SpaceX is ready
and with complete confidence in the rocket, spaceship and operations.”
Given SpaceX’s high flight rate and the ability to launch
its own payloads — Starlinks — the company may be able to recover in fairly
short order. But that will depend on what went wrong, what might be needed to
fix it and when the FAA grants a new launch license.
SpaceX founder Elon Musk thanked Isaacman for his support,
saying the company “will investigate the issue and look for any other potential
near-misses. We are tracking to do more Falcon flights this year than shuttle
did in 30 years, the vast majority of which are uncrewed.”
“A major advantage of this super-high flight rate is that we
can identify and resolve problems that may only occur once every 1,000 flights.
This is impossible on a low-flight-rate vehicle.”
However it plays out, the incident underscores NASA’s
ongoing push to certify Boeing’s Starliner capsule after its ongoing test
flight is complete. The space agency wants two crew ferry ships from different
suppliers to keep the International Space Station staffed with NASA astronauts
if a failure grounds one or the other.
Boeing has had its own problems with the Starliner,
including a series of software and hardware problems that delayed launch by
four years. The spacecraft is currently is docked at the space station, but its
return to Earth from its first piloted test flight is on hold pending
additional analysis of helium leaks and problems with its thrusters.
Prior to Thursday’s launch, SpaceX had suffered just one
in-flight failure in 354 launches of Falcon 9 and Falcon Heavy rockets dating
back to the system’s maiden flight in 2010.
A Falcon 9 carrying a Dragon cargo ship loaded with supplies
and equipment bound for the International Space Station exploded during launch
in June 2015 when an internal strut failed, allowing high-pressure helium to
rupture the second stage’s liquid oxygen tank.
In a post on his social media platform early Friday, Musk
said the Starlink launch failure occurred during an attempt to restart the
rocket’s second stage Merlin engine to put the craft in the proper Starlink
deploy orbit.
He Initially said the failure resulted in “an engine RUD,” a
tongue-in-cheek acronym that stands for “rapid unscheduled disassembly,”
implying the stage either blew up or at least suffered some sort of structural
failure.
But the company said later the failure was the result of a
liquid oxygen propellant leak and that the stage survived the aborted engine
firing. But while it managed to deploy the Starlinks, they were left in an
elliptical orbit with a low point far below a manageable altitude.
“After a planned relight of the upper stage engine to raise
perigee — or the lowest point of orbit — the Merlin Vacuum engine experienced
an anomaly and was unable to complete its second burn,” SpaceX said on its
website
“Although the stage survived and still deployed the
satellites, it did not successfully circularize its orbit. This left the
satellites in an eccentric orbit with a very low perigee of 135 kilometers (84
miles), which is less than half the expected perigee altitude.”
In that altitude, the satellites are being pulled down
during repeated passages through the extreme upper atmosphere. Even at full
power, the thrust from onboard ion thrusters is unlikely to be sufficient to
successfully raise the satellites.
“As such, the satellites will re-enter Earth’s atmosphere
and fully demise (burn up). They do not pose a threat to other satellites in
orbit or to public safety.”